Wheat Sown with Narrow Spacing Results in Higher Yield and Water Use Efficiency under Deficit Supplemental Irrigation at the Vegetative and Reproductive Stage

Abstract

A decrease in water resources around the globe in irrigated agriculture has resulted in a steep decline in irrigation water availability. Therefore, management options for efficient use of available irrigation water are inevitable. Deciding the critical time, frequency and amount of irrigation are compulsory to achieve higher crop outputs. Hence, this two-year field study was conducted to assess the role of different row spacings, i.e., 20, 25 and 30 cm, on growth, productivity, and water use efficiency (WUE) of wheat under deficit supplemental irrigation (DSI) at the vegetative and reproductive phase by using surplus supplemental irrigation (SSI) throughout the growing season as the control. DSI at both growth stages, and the reproductive stage in particular, changed the crop allometry, yield and net income of wheat. However, narrow spacing (20 cm) resulted in efficient use of available irrigation water (DSI and SSI) with higher yield, WUE and economic returns. Interestingly, wider spacing resulted in a higher number of grains per spike with higher 1000-grain weight under SSI and DSI, but final yield output remained poor due to a lower number of productive tillers. It was concluded that reducing irrigation during the vegetative stage is less damaging compared with the reproductive phase; therefore, sufficient supplemental irrigation must be added at the reproductive stage, particularly during grain-filling. Further, narrow spacing (20 cm) resulted in efficient utilization of available irrigation water; therefore, wheat must be grown at a narrow spacing to ensure the efficient utilization of available irrigation water.

The impact of different weed management strategies on weed flora of wheat-based cropping systems

“…Nonetheless, wheat production is becoming stagnant in several regions of the world [ 9 ]. Delayed harvesting of kharif crops [ 10 ], use of old varieties [ 10 ], improper seed rate and row spacing [ 11 – 15 ], poor fertilizer use efficiency [ 16 ], weed infestation [ 17 ] and drought stress [ 18 , 19 ] are regarded as the main reasons of stagnant wheat yields.…”

Teff [Eragrostis tef (Zucc.)] rainfed yield response to planting method, seeding density, and row spacing

“…Therefore, grain yield decreased as RS increased beyond 15 cm. Although similar studies of teff are lacking, previous studies of other cereals indicated that narrow RS can maximize yield in wheat (Hussain et al., 2016), rice (Chauhan & Johnson, 2011) and finger millet ( Eleucine coracana ; Shinggu et al., 2009). Fischer, Ramos, Monasterio, and Sayre (2019) reported that a significant grain yield reduction was observed in wheat for RS beyond 30 cm.…”

Modern wheat semi-dwarfs root deep on demand: response of rooting depth to drought in a set of Swiss era wheats covering 100 years of breeding

“…To avoid negative effects of small pot sizes, such as restricted root zones leading to water and nutrient limitations, a column depth of 160 cm was chosen. It is known that plant density and pot size affect plant growth and root-shoot ratios (Krizek et al 1985;Hussain et al 2016;Poorter et al 2012). Poorter et al (2012) highlighted that root mass increases with smaller pot size, but decreases shoot biomass due to limited nutrient and water availability.…”